Binge eating is a common problem associated with obesity and with increased risk for psychiatric and medical morbidity and is recognized as a significant health problem. Cognitive behavioral therapy (CBT) and certain medications have been found to be effective for treating binge eating in several controlled studies at specialized research clinics. Whether such treatments can be effectively administered in non-specialist primary care settings is unknown. Research has documented that recurrent binge eating in obese persons is associated with high healthcare utilization but infrequently with receipt of treatments with demonstrated efficacy. This study aims to examine whether such efficacious treatments, if suitably adapted, can be effectively administered in primary care settings. The study will test the effectiveness of two treatments: CBT using a pure-self help approach (CBTsh) and sibutramine (anti-obesity medication) also found to be effective for reducing binge eating. 150 obese patients with recurrent binge eating (without inappropriate weight control behaviors) will be treated by non-specialist clinicians in primary care settings. Participants will be randomized to one of four treatments (balanced 2-by-2 factorial design) for 16 weeks: (1) sibutramine (15 mg/d) (2) placebo;(3) CBTsh and sibutramine (15 mg/d) placebo;or (4) CBTsh and placebo. Medication will be given in double-blind fashion with minimal clinical management. Thus, treatments are closely matched in clinical time to control partly for attention and, more importantly, to reflect the clinical reality of their potential use in busy primary care settings. Changes throughout the course of treatments will be evaluated and major outcome assessments will be performed by independent evaluators at the end of active treatment (4 months) and at 6- and 12-months after ending treatments (10 and 16 months after randomization). Comprehensive evaluations will assess both binge eating and obesity and their associated outcomes (features of eating disorders, psychological functioning, biological variables) and will allow for exploration of mediators and moderators of outcomes. This study, only the second controlled trial of CBT and a medication alone and in combination for binge eating in obese patients, will provide important information about the utility of specific treatments for use by non-specialists in primary care settings. This study will provide needed information about the durability or maintenance of these treatments for the year following treatment completion.